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A bad sex epidemic is plaguing the bedrooms of lovers all across the nation: the orgasm gap. Men, whether gay, bisexual, or heterosexual, are twice as likely to climax as women, and science has shed light on why. A recent study published in the Journal of Sex Research found women turn down oral sex from straight men to avoid returning the favor.

“It seems that women may be reluctant to ask for oral sex from their male partners because they are not overly keen on reciprocating the act," Karen L. Blair of St. Francis Xavier University, the study’s corresponding author, told PsyPost.

Researchers at St. Francis Xavier University and Queens University found straight men would really like to perform oral sex on their partner more often. However, there are two possible ulterior motives: men could want to give oral more, but can't because their partners are reluctant; or men would like to receive more oral sex, and they believe to do so, they should provide it first.

Yet, Blair highlights women are already “reciprocating" via vaginal penetration, the most enjoyable form of orgasm for men. For women “to also experience their most satisfying orgasm, the reciprocation from their male partner should likely be performing oral sex.”

Most women need direct clitoral stimulation to have an orgasm. Previous research has found the combination of oral sex with vaginal intercourse increases the likelihood of climax, but since few women opt for oral sex, this reduces the odds. This is only found to be applicable in mixed-sex relationships.

Meanwhile, women in same-sex relationships report greater frequency of orgasm from clitoral stimulation. But, there was no difference between women in same-sex and mixed-sex relationships when it came to the frequency of orgasms from vaginal intercourse combined with clitoral stimulation. This suggests women in same-sex relationships may be more attuned with other women's bodies, hence they're better equipped to pleasure other women's bodies as they would their own.

Overall, men and women in same-sex relationships reported a greater frequency of oral sex than those in mixed-sex relationships. The researchers believe those in same-sex relationships are more successful at achieving orgasm, because there are no "sexual scripts" from society or the media to tell them what works or doesn't work.

"They always had to find out what each new partner liked or didn’t like, which possibly makes it easier for same-sex couples to craft individualized sexual scripts that work best for each new relationship," said Blair.

In the study, over 800 adults in romantic relationships, including men in mixed-sex relationships, men in same-sex relationships, women in mixed-sex relationships, and women in same-sex relationships, were examined. Half of the participants identified with the labels gay or lesbian, while about 5 percent identified as bisexual. The findings were all based on averages, but it's important to note each partner will have their own preferences.

Blair’s findings coincide with previous findings on the orgasm gap. For example, in a 2005 study, researchers found a 52 percent orgasm gap existed among 800 college students. This means 39 percent of women and 91 percent of men said they usually, or always, experienced orgasm in partnered sex. Interestingly, another study with 15,000 college students found the gap was larger in hookup sex than relationship sex.

To bridge the orgasm gap, men need to understand the key to the female orgasm is knowing your partner. Foreplay minutes or hours before sex should stimulate your partner both physically and emotionally. This can get anyone in the mood.

Source: Blair KL, Cappell J, and Pukall CF. Not All Orgasms Were Created Equal: Differences in Frequency and Satisfaction of Orgasm Experiences by Sexual Activity in Same-Sex versus Mixed-Sex Relationships. Journal of Sex Research. 2017.